A runner in Springtime needs to be prepared for anything: rain, wind, sun and sleet. To help manage the unpredictable elements, Nike Sphere technology provides the desired warmth without unnecessary weight. The innovative fabric uses a 3-D structure to create space between the body and the garment, where air can be held and warmed by the body’s own natural heat. The fabric’s structure also allows moisture to escape, helping to maintain excellent breathability.